43.6.1 Principle of Operation

Important: When AVDD < 2.5v, for proper ADC operation it is critical that the internal charge pumps be enabled as necessary as define in SUPC.VREGCTRL.CPEN[1:0].

The basic architecture of an ADC Module is shown in the following figure.

At the start of a capture cycle the Sample and Hold capacitor is connected to the incoming voltage on a trigger event until the expiration of the sample time defined by CORCTRLx.SAMC. At the end of the sampling period the Sample and Hold is disconnected from the input signal and connected to the Comparator and the conversion sequence begins. ADC conversion time = (# bits +1)*TAD).

Figure 43-3. ADC Module Architecture